(1) Field of The Invention
This invention pertains to an apparatus which transports cementitious material from a bulk supply of materials directly to a hawk whereon a supply of the material accumulates for application to a surface by a skilled workman with a trowel.
(2) Description of Prior Art
Cementitious materials, including but not limited to such materials as stucco and plaster, have traditionally been applied to both interior and exterior wall or ceiling surfaces with a trowel. The supply of cementitious material used by the said skilled workman is held on a hawk, which is comprised of a square plane metal surface below which and perpendicular thereto, a handle is mounted. The skilled workman typically holds the hawk in one hand and scoops cementitious material from the hawk with the trowel.
To replenish the material on the hawk, the skilled workman frequently supplies materials to the hawk from a nearby table on which cementitious material is stored. This storage table or mud board is typically replenished continually by other unskilled workers who move the cementitious materials from a mixer to said mud board by wheelbarrow, shovel, and the like. For work done above the first story, the cementitious material is transported to the elevated workplace by means of buckets, pulleys, and shovels.
The application of cementitious materials, as presently done and described above, entails the need for numerous unskilled workmen to supply the cementitious material to the workplace of the skilled workman. It furthermore requires that the skilled workman applying the material to the surface, who is skilled and trained in this trade, must frequently replenish his supply of cementitious material on his hawk by stopping what he is doing when he has used up the cementitious material on his hawk, walking to the material storage table or mud board where he places cementitous material on his hawk, and returning to his workplace to again apply this material to the surface with the trowel.
Delivery of plaster and similar materials directly to the hawk or to the trowel are known. However, all of these provide for a valve at or near the hawk or trowel, thereby causing pressure to build up in the flow line hose and hence cause surging or squirting of the cementitious material from the hawk or trowel surface. See U.S. Pat. No. 2,535,726 wherein a hawk is described which is equipped with a mechanical valve to control the flow of fluid plaster delivered thereto. See also U.S. Pat. No. 3,403,960 wherein a trowel is equipped with a mechanical valve at the trowel, and the apparatus therein described is designed to overcome surges in the flow. A further problem with such systems is that the cementitious material is caused to lose water at the valve, should it leak. This water loss causes the cementitious material to cake up and form a hard mass which restricts the continuing flow of cementitious material and, hence, causes the line to plug up or the valve to seize up. The occurrence of water loss and formation of cake buildup is also known to occur at points in the flowing line where the cross-section in said line is suddenly reduced. As a result of these shortcomings, none of these means of delivery directly to the hawk or trowel are in significant commercial use.
Unlike these previous embodiments, flow in this invention is unobstructed with flow lines of essentially constant cross-section and flow controlled at the pump directly by the skilled workman who is applying said cementitious material. Pressure in the flowing system is due primarily to hydrostatic head of the cementitious material, and hence, surging squirting and filter cake buildup are thereby eliminated.